qt6-bb10/src/corelib/kernel/qelapsedtimer_win.cpp

124 lines
3.0 KiB
C++

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qelapsedtimer.h"
#include "qdeadlinetimer.h"
#include "qdeadlinetimer_p.h"
#include <qt_windows.h>
QT_BEGIN_NAMESPACE
// Result of QueryPerformanceFrequency
static quint64 counterFrequency = 0;
static void resolveCounterFrequency()
{
static bool done = false;
if (done)
return;
// Retrieve the number of high-resolution performance counter ticks per second
LARGE_INTEGER frequency;
if (!QueryPerformanceFrequency(&frequency) || frequency.QuadPart == 0)
qFatal("QueryPerformanceFrequency failed, even though Microsoft documentation promises it wouldn't.");
counterFrequency = frequency.QuadPart;
done = true;
}
static inline qint64 ticksToNanoseconds(qint64 ticks)
{
// QueryPerformanceCounter uses an arbitrary frequency
qint64 seconds = ticks / counterFrequency;
qint64 nanoSeconds = (ticks - seconds * counterFrequency) * 1000000000 / counterFrequency;
return seconds * 1000000000 + nanoSeconds;
}
static quint64 getTickCount()
{
resolveCounterFrequency();
LARGE_INTEGER counter;
bool ok = QueryPerformanceCounter(&counter);
Q_ASSERT_X(ok, "QElapsedTimer::start()",
"QueryPerformanceCounter failed, although QueryPerformanceFrequency succeeded.");
Q_UNUSED(ok);
return counter.QuadPart;
}
quint64 qt_msectime()
{
return ticksToNanoseconds(getTickCount()) / 1000000;
}
QElapsedTimer::ClockType QElapsedTimer::clockType() noexcept
{
resolveCounterFrequency();
return PerformanceCounter;
}
bool QElapsedTimer::isMonotonic() noexcept
{
return true;
}
void QElapsedTimer::start() noexcept
{
t1 = getTickCount();
t2 = 0;
}
qint64 QElapsedTimer::restart() noexcept
{
qint64 oldt1 = t1;
t1 = getTickCount();
t2 = 0;
return ticksToNanoseconds(t1 - oldt1) / 1000000;
}
qint64 QElapsedTimer::nsecsElapsed() const noexcept
{
qint64 elapsed = getTickCount() - t1;
return ticksToNanoseconds(elapsed);
}
qint64 QElapsedTimer::elapsed() const noexcept
{
qint64 elapsed = getTickCount() - t1;
return ticksToNanoseconds(elapsed) / 1000000;
}
qint64 QElapsedTimer::msecsSinceReference() const noexcept
{
return ticksToNanoseconds(t1) / 1000000;
}
qint64 QElapsedTimer::msecsTo(const QElapsedTimer &other) const noexcept
{
qint64 difference = other.t1 - t1;
return ticksToNanoseconds(difference) / 1000000;
}
qint64 QElapsedTimer::secsTo(const QElapsedTimer &other) const noexcept
{
return msecsTo(other) / 1000;
}
bool operator<(const QElapsedTimer &v1, const QElapsedTimer &v2) noexcept
{
return (v1.t1 - v2.t1) < 0;
}
QDeadlineTimer QDeadlineTimer::current(Qt::TimerType timerType) noexcept
{
static_assert(!QDeadlineTimerNanosecondsInT2);
QDeadlineTimer result;
result.t1 = ticksToNanoseconds(getTickCount());
result.type = timerType;
return result;
}
QT_END_NAMESPACE